LPS produces ALI, increased blood NPA and MPA, and the intra-alveolar accumulation of platelets and NPA; ASA attenuates these responses. (A) BAL WBC and neutrophil counts, (B) MPO activity in the cell-free BAL, and (C) lung protein permeability in PBS and LPS-challenged mice + ASA vs vehicle (DMSO) controls. **P < .01, ****P < .0001 vs vehicle groups and †††P < .001, ††††P < .0001 vs PBS. (D) Densitometric analysis and representative membrane of blots against CD41 protein performed on BAL cells in PBS controls and LPS + ASA vs vehicle group. ††††P < .0001 and ****P < .0001 vs PBS and vehicle, respectively. (E) CD41 (and isotype control) flow cytometry analysis in BAL cells from mice with no LPS and LPS ± ASA with representative histogram plots and MFI (representative of 5 independent experiments). (F) TXB₂ levels in cell-free BAL from control and LPS + ASA vs vehicle groups. †P < .05 vs PBS; **P < .05 vs vehicle. (G) Percentage NPAs and (H) percentage MPAs in whole blood at different time points after LPS instillation and effects of ASA treatment at indicated times. ††P < .01, †††P < .001, and ††††P < .0001 vs PBS; and **P < .01 and ****P < .0001 vs LPS-challenged mice at 48 hours. (I) Percentage NPAs in BAL after LPS + ASA vs vehicle (at 48 hours). *P < .05 vs vehicle. Data are mean ± SD of 5 to 10 animals per group.